
.form{background: rgba(255,255,255,0.2);width:400px;margin:120px auto;}
/*阴影*/
.fa{display: inline-block;top: 27px;left: 6px;position: relative;color: #ccc;}
input[type="text"],input[type="password"]{padding-left:26px;}
.checkbox{padding-left:21px;}


html,
body {
    width: 100%;
    height: 100%;
    margin: 0;
    overflow: hidden;
    background: linear-gradient(rgba(0, 108, 172, 1), rgba(0, 122, 195, .7));
}
#stars {
    margin: 0 auto;
    max-width: 1600px;
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    z-index: 2;
}
.star {
    display: block;
    width: 1px;
    background: transparent;
    position: relative;
    opacity: 0;
    /*过渡动画*/

    animation: star-fall 3s linear infinite;
    -webkit-animation: star-fall 3s linear infinite;
    -moz-animation: star-fall 3s linear infinite;
}
.star:after {
    content: '';
    display: block;
    border: 0px solid #fff;
    border-width: 0px 90px 2px 90px;
    border-color: transparent transparent transparent rgba(255, 255, 255, .5);
    box-shadow: 0 0 1px 0 rgba(255, 255, 255, .1);
    /*变形*/

    transform: rotate(-45deg) translate3d(1px, 3px, 0);
    -webkit-transform: rotate(-45deg) translate3d(1px, 3px, 0);
    -moz-transform: rotate(-45deg) translate3d(1px, 3px, 0);
    transform-origin: 0% 100%;
    -webkit-transform-origin: 0% 100%;
    -moz-transform-origin: 0% 100%;
}
@keyframes star-fall {
    0% {
        opacity: 0;
        transform: scale(0.5) translate3d(0, 0, 0);
        -webkit-transform: scale(0.5) translate3d(0, 0, 0);
        -moz-transform: scale(0.5) translate3d(0, 0, 0);
    }
    50% {
        opacity: 1;
        transform: translate3d(-200px, 200px, 0);
        -webkit-transform: translate3d(-200px, 200px, 0);
        -moz-transform: translate3d(-200px, 200px, 0);
    }
    100% {
        opacity: 0;
        transform: scale(1.2) translate3d(-300px, 300px, 0);
        -webkit-transform: scale(1.2) translate3d(-300px, 300px, 0);
        -moz-transform: scale(1.2) translate3d(-300px, 300px, 0);
    }
}